• Title/Summary/Keyword: Group movement

Search Result 1,803, Processing Time 0.027 seconds

The Research on Online Game Hedonic Experience - Focusing on Moderate Effect of Perceived Complexity - (온라인 게임에서의 쾌락적 경험에 관한 연구 - 지각된 복잡성의 조절효과를 중심으로 -)

  • Lee, Jong-Ho;Jung, Yun-Hee
    • Journal of Global Scholars of Marketing Science
    • /
    • v.18 no.2
    • /
    • pp.147-187
    • /
    • 2008
  • Online game researchers focus on the flow and factors influencing flow. Flow is conceptualized as an optimal experience state and useful explaining game experience in online. Many game studies focused on the customer loyalty and flow in playing online game, In showing specific game experience, however, it doesn't examine multidimensional experience process. Flow is not construct which show absorbing process, but construct which show absorbing result. Hence, Flow is not adequate to examine multidimensional experience of games. Online game is included in hedonic consumption. Hedonic consumption is a relatively new field of study in consumer research and it explores the consumption experience as a experiential view(Hirschman and Holbrook 1982). Hedonic consumption explores the consumption experience not as an information processing event but from a phenomenological of experiential view, which is a primarily subjective state. It includes various playful leisure activities, sensory pleasures, daydreams, esthetic enjoyment, and emotional responses. In online game experience, therefore, it is right to access through a experiential view of hedonic consumption. The objective of this paper was to make up for lacks in our understanding of online game experience by developing a framework for better insight into the hedonic experience of online game. We developed this framework by integrating and extending existing research in marketing, online game and hedonic responses. We then discussed several expectations for this framework. We concluded by discussing the results of this study, providing general recommendation and directions for future research. In hedonic response research, Lacher's research(1994)and Jongho lee and Yunhee Jung' research (2005;2006) has served as a fundamental starting point of our research. A common element in this extended research is the repeated identification of the four hedonic responses: sensory response, imaginal response, emotional response, analytic response. The validity of these four constructs finds in research of music(Lacher 1994) and movie(Jongho lee and Yunhee Jung' research 2005;2006). But, previous research on hedonic response didn't show that constructs of hedonic response have cause-effect relation. Also, although hedonic response enable to different by stimulus properties. effects of stimulus properties is not showed. To fill this gap, while largely based on Lacher(1994)' research and Jongho Lee and Yunhee Jung(2005, 2006)' research, we made several important adaptation with the primary goal of bringing the model into online game and compensating lacks of previous research. We maintained the same construct proposed by Lacher et al.(1994), with four constructs of hedonic response:sensory response, imaginal response, emotional response, analytical response. In this study, the sensory response is typified by some physical movement(Yingling 1962), the imaginal response is typified by images, memories, or situations that game evokes(Myers 1914), and the emotional response represents the feelings one experiences when playing game, such as pleasure, arousal, dominance, finally, the analytical response is that game player engaged in cognition seeking while playing game(Myers 1912). However, this paper has several important differences. We attempted to suggest multi-dimensional experience process in online game and cause-effect relation among hedonic responses. Also, We investigated moderate effects of perceived complexity. Previous studies about hedonic responses didn't show influences of stimulus properties. According to Berlyne's theory(1960, 1974) of aesthetic response, perceived complexity is a important construct because it effects pleasure. Pleasure in response to an object will increase with increased complexity, to an optimal level. After that, with increased complexity, pleasure begins with a linearly increasing line for complexity. Therefore, We expected this perceived complexity will influence hedonic response in game experience. We discussed the rationale for these suggested changes, the assumptions of the resulting framework, and developed some expectations based on its application in Online game context. In the first stage of methodology, questions were developed to measure the constructs. We constructed a survey measuring our theoretical constructs based on a combination of sources, including Yingling(1962), Hargreaves(1962), Lacher (1994), Jongho Lee and Yunhee Jung(2005, 2006), Mehrabian and Russell(1974), Pucely et al(1987). Based on comments received in the pretest, we made several revisions to arrive at our final survey. We investigated the proposed framework through a convenience sample, where participation in a self-report survey was solicited from various respondents having different knowledges. All respondents participated to different degrees, in these habitually practiced activities and received no compensation for their participation. Questionnaires were distributed to graduates and we used 381 completed questionnaires to analysis. The sample consisted of more men(n=225) than women(n=156). In measure, the study used multi-item scales based previous study. We analyze the data using structural equation modeling(LISREL-VIII; Joreskog and Sorbom 1993). First, we used the entire sample(n=381) to refine the measures and test their convergent and discriminant validity. The evidence from both the factor analysis and the analysis of reliability provides support that the scales exhibit internal consistency and construct validity. Second, we test the hypothesized structural model. And, we divided the sample into two different complexity group and analyze the hypothesized structural model of each group. The analysis suggest that hedonic response plays different roles from hypothesized in our study. The results indicate that hedonic response-sensory response, imaginal response, emotional response, analytical response- are related positively to respondents' level of game satisfaction. And game satisfaction is related to higher levels of game loyalty. Additionally, we found that perceived complexity is important to online game experience. Our results suggest that importance of each hedonic response different by perceived game complexity. Understanding the role of perceived complexity in hedonic response enables to have a better understanding of underlying mechanisms at game experience. If game has high complexity, analytical response become important response. So game producers or marketers have to consider more cognitive stimulus. Controversy, if game has low complexity, sensorial response respectively become important. Finally, we discussed several limitations of our study and suggested directions for future research. we concluded with a discussion of managerial implications. Our study provides managers with a basis for game strategies.

  • PDF

M-mode Ultrasound Assessment of Diaphragmatic Excursions in Chronic Obstructive Pulmonary Disease : Relation to Pulmonary Function Test and Mouth Pressure (만성폐쇄성 폐질환 환자에서 M-mode 초음파로 측정한 횡격막 운동)

  • Lim, Sung-Chul;Jang, Il-Gweon;Park, Hyeong-Kwan;Hwang, Jun-Hwa;Kang, Yu-Ho;Kim, Young-Chul;Park, Kyung-Ok
    • Tuberculosis and Respiratory Diseases
    • /
    • v.45 no.4
    • /
    • pp.736-745
    • /
    • 1998
  • Background: Respiratory muscle interaction is further profoundly affected by a number of pathologic conditions. Hyperinflation may be particularly severe in chronic obstructive pulmonary disease(COPD) patients, in whom the functional residual capacity(FRC) often exceeds predicted total lung capacity(TLC). Hyperinflation reduces the diaphragmatic effectiveness as a pressure generator and reduces diaphragmatic contribution to chest wall motion. Ultrasonography has recently been shown to be a sensitive and reproducible method of assessing diaphragmatic excursion. This study was performed to evaluate how differences of diaphragmatic excursion measured by ultrasonography associate with normal subjects and COPD patients. Methods: We measured diaphragmatic excursions with ultrasonography on 28 healthy subjects(l6 medical students, 12 age-matched control) and 17 COPD patients. Ultrasonographic measurements were performed during tidal breathing and maximal respiratory efforts approximating vital capacity breathing using Aloka KEC-620 with 3.5 MHz transducer. Measurements were taken in the supine posture. The ultrasonographic probe was positioned transversely in the midclavicular line below the right subcostal margin. After detecting the right hemidiaphragm in the B-mode the ultrasound beam was then positioned so that it was approximately parallel to the movement of middle or posterior third of right diaphragm. Recordings in the M-mode at this position were made throughout the test. Measurements of diaphragmatic excursion on M-mode tracing were calculated by the average gap in 3 times-respiration cycle. Pulmonary function test(SensorMedics 2800), maximal inspiratory(PImax) and expiratory mouth pressure(PEmax, Vitalopower KH-101, Chest) were measured in the seated posture. Results: During the tidal breathing, diaphragmatic excursions were recorded $1.5{\pm}0.5cm$, $1.7{\pm}0.5cm$ and $1.5{\pm}0.6cm$ in medical students, age-matched control group and COPD patients, respectively. Diaphragm excursions during maximal respiratory efforts were significantly decreased in COPD patients ($3.7{\pm}1.3cm$) when compared with medical students, age-matched control group($6.7{\pm}1.3cm$, $5.8{\pm}1.2cm$, p< 0.05}. During maximal respiratory efforts in control subjects, diaphragm excursions were correlated with $FEV_1$, FEVl/FVC, PEF, PIF, and height. In COPD patients, diaphragm excursions during maximal respiratory efforts were correlated with PEmax(maximal expiratory pressure), age, and %FVC. In multiple regression analysis, the combination of PEmax and age was an independent marker of diaphragm excursions during maximal respiratory efforts with COPD patients. Conclusion: COPD subjects had smaller diaphragmatic excursions during maximal respiratory efforts than control subjects. During maximal respiratory efforts in COPD patients, diaphragm excursions were well correlated with PEmax. These results suggest that diaphragm excursions during maximal respiratory efforts with COPD patients may be valuable at predicting the pulmonary function.

  • PDF

The Study about 「The Discourse on the Constitutional Symptoms and Diseases」 of Sasangin on the 『Dongyi Suse Bowon』 (『동의수세보원(東醫壽世保元)』 태소음양인(太少陰陽人)의 「병증론(病證論)」에 관(關)한 연구(硏究))

  • Lee, Su-kyung;Song, Il-byung
    • Journal of Sasang Constitutional Medicine
    • /
    • v.11 no.2
    • /
    • pp.1-26
    • /
    • 1999
  • This paper was written in order to understand each constitutional symptoms and diseases with two aspects. The first was to trace the courses to accomplish constitutional symptoms and diseases from that of oriented medicine through "Dongyi Bogam" and the original writing such as "Shanghanlun". The second was to analyze the constitutional diseases with Lee Je-ma's own recognition on human being and the society which was based on the "Dongyi Suse Bowon". The original concepts of 'The Interior Disease' and 'The Exterior Disease' were based on the Nature and the Emotion, the Environmental Frames and the Human Affairs, the Ears Eyes Nose Mouth and the Lung Spleen Liver Kidney. The exterior disease were caused by the abilities of ears to listen, eyes to see, nose to smell, and mouth to taste on the environmental frames which were related one's recognition to society. The interior diseases were caused by the abilities of lung to study, spleen to ask, liver to think, kidney to judge on human affairs which were related the relationship between me and others. So the titles of constitutional diseases were named by these views on his first writing of "Dongyi Suse Bowon" in 1894. So the titles of Taeyangin diseases, 'The lumbar Vertebae Disease Induced by Exopathogen' and 'The Small Intestine Disease Induced by Endopathogen' were still remained as the first writing. But the titles of constitutional diseases were rewritten such as present titles in 1900. In order to express pathology and mechanism of constitutional diseases exactly, he rewrote titles which contained the manifestation sites of diseases, and the symptoms of febrile and cold, and the different congenital formations of organs. The exterior diseases and interior diseases had three characteristics. The first was that the exterior disease injured by the nature which had a tendency to progress slowly and the interior disease injured by the emotion which had a tendency to progress rapidly. The second was not that the interior disease and the exterior disease were separated, but that one influenced the other and these were revealed as a disease together when the diseases continued for a long time. The third was that even though the disease caught together it was included the beginning disease. The symptoms in ordinary times was the origin and clue to recognize the constitutional symptoms and diseases. It enabled to establish the constitutional medicine which treated by different ways according to constitution. It had two characteristics which were different from the Traditional Chinese Medicine in appearance of diseases. The first was that the disease was progressed to the next step from the symptoms in ordinary times. The second was that each constitution had different symptoms which were due to symptoms in ordinary times under the same disease, The third was the manifestation of disease were different from symptoms in ordinary times in the same constitution. But the most important thing was that Lee Je-ma recognized these symptoms in ordinary times as four categories and he presented constitutional symptoms and constitutional disease. The four categories were the method to recognize the human being and the diseases for him As the symptoms and diseases of Sasang Constitutional Medicine were compared to Traditional Chinese Medicine, the constitutional diseases of "Dongyi Suse Bowon" could be classified into two groups. The first group was the unique diseases and symptoms, which were not in the Traditional Chinese Medicine, and which were established by the Lee Je-ma. These contained the diseases of taeyangin, the exterior disease of taeumin, the exterior disease of soyangin. The second group used the unique methods to treat disease, which were not in Traditional Chinese Medicine, and which were established by Lee Je-ma. This contained the interior disease of taeumin, the delirium diseases from the MangYin of soyangin, the treatment to help the Yang-Qi ascend and to supplement the ql In the exterior disease of soeumin. Especially, the diseases of taeyangin and taeumin which were caused by the metabolism disorders of Qi-Yack(氣液) were the great achievement to establish constitutional symptoms and diseases. The discourse of taeyangin diseases presented his original thought to recognize the symptoms and diseases through the Shin Gi Hyul Jeong(神氣血精) and the Qi-Yack, the discourse of taeumin diseases presented the disperse of Qi-Yack through the forward and backward of sweat, the discourse of soyangin disease presented the sweat of hand and feet which was manifested that yin-qi of spleen descended to yin qi of kidney, and the bowel movement which was manifested that yang qi of large intestine ascend to head, face and four extremities, the discourse of soeumin disease presented the Jueyin syndrome without the abdominal pain and diarrhea as the exterior disease and made importance to the nervous mind And the classification of exterior diseases and interior diseases were not due to the pharmacology but due to the symptoms and diseases according to the constitution.

  • PDF

Sociopsychological Factors related to Prediction of Treatment Outcome of the Temporomandibular Disorders (측두하악장애 치료결과의 예측에서 사회심리학적 요인의 영향)

  • Yeo, In-Sik;Han, Kyung-Soo;Kim, Yun-Hee
    • Journal of Oral Medicine and Pain
    • /
    • v.30 no.4
    • /
    • pp.433-446
    • /
    • 2005
  • The purpose of this study was to investigate the sociopsychological factors which might influence the course of the temporomandibular disorders and to develop models for prediction of treatment outcome related to pain, dysfunction and sound. For this study, 268 patients with temporomandibular disorders were selected from the patients presented to department of Oral Medicine, Wonkwang university dental hospital. Chief complaints of these subjects were largely grouped into three categories such as pain, dysfunction and sound, and 10 cm visual analogue scale(VAS) was used to record the state of the three complaints every visit and Treatment Index(VAS TI) was calculated from VAS. All the forty-two items obtained from clinical examination or questionnaire were statistically processed with $SPSS^{(R)}$ windows. The results of this study were as follows: 1. The items showed a difference between male and female subjects were maximum mouth opening, palpation score, jaw jerk during mandibular movement, and sleep disturbance. Among questionnaires such as SRRS, HAD scale and PSQI, the HAD scales showed the most highly significant correlation with the each scale item of the SCL-90R. 2. Among the groups classified by VAS TI, the group with the lowest VAS TI showed the highest VAS score in the start of treatment but showed the lowest score in the end of treatment, without respect to the type of chief complaint. From these results, it is assumed that the active treatment duration for the subjects with lower VAS score in the first visit would be longer than the subjects with higher score with the somewhat poor treatment outcome. 3. With regard to all the three complaints, the items showing significant effect in the model for prediction of treatment outcome were from questionnaire, except one item, maximum mouth opening, which suggest that the sociopsychological factors would be strongly related to development and progress of the symptoms.

A STUDY ON THE FOOD OF THE GOBY, SYNECHOGOBIUS HASTA (풀망둑 Synechogobius hasta (TEMMINCK et SCHLEGEL)의 먹이 조사)

  • PAIK Eui-In
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.2 no.1
    • /
    • pp.47-62
    • /
    • 1969
  • A goby, Synechogobius hasta (Temminck et Schlegel) was studied to investigate the food consumed and the biological change of the food organisms, and the fish were sampled from the closed tributary and the lower Part of the Naktong River, near Pusan, during the period from November of 1967 to December of 1968. The fish were sampled from four stations (Fig. 1), the total number of fish being 1,295 and they were grouped and analysed monthly. The content of the alimentary canal was analysed in three categories according to modified Nilsson's method (Dahl 1962) with a slight alteration: 1) The number of each item of stomach contents was counted and the percentage of each item in proportion to the total number of food organisms is indicated by the letter 'N' representing numerical percentage in Table 2. 2) The percentage of fish which contained any items of food organisms in proportion to the total number of fish caught in a given season is indicated by the letter 'O' representing frequency of occurrence. 3) Dominant groups of food items were selected and the percentage of the number of each dominant item in proportion to the number of the food organisms belonging to the dominant groups is indicated by the letter 'D' representing dominance. All food organisms were classified in 50 food item categories and then they were grouped in 13 main groups (Fig. 2-1), and they were further divided into 1) obligatory bottom animals, 2) organic drifts and 3) actively swimming forms; according to the conditions of the animal communities within the habitat. Since the majority of its food was composed of the obligatory bottom animals ($94.6\%$), the fish appeard to be a typical bottom feeder. And the dominant food organisms of the fish is generally determined by the local composition of the benthic fauna within the fish habitat. And their seasonal rhythm occurs among the food organisms in the stomach by the biological interaction. Locality variation in the population of the same food organism occurs due to the difference of food organisms in the habitat of the fish at Seonam and Garak, and at Seongsan and Hadan the condition of the niche for the fish in the both regions seems to be the same since the composition and the seasonal variation of the organisms were the same. The results may be summarized as follows: 1) The goby mainly feed on the animals of bottom fauna, and the food organisms are deter-mined by the food compositions within the habitat. 2) Seasonal variation of the stomach content shows the seasonal rhythm due to the biological variation of the population and their interaction. 3) The goby shows no preference on specific food, and the food is composed of a variety of animals. 4) Major food items of the goby are Polychaeta, Palaemon modestus, Isopoda, Gammaridea, Insecta (nymphs and larvae), Ilyoplax deschampsi, and Paratye compressa. 5) Logitudinal succession oil the population of the food organisms is apparently recognized within the community of Seongsan, Garak and Seonam. 6) The goby begins to descend toward the estuary and sea around April when the water temperature reaches $20^{\circ}C$, and they begin to return to river waters in September.

  • PDF

A Case Study on the Preservation Strategies of 'Historic Urban Parks' in the UK, the USA, and Japan (영국, 미국, 일본의 '역사적 도시공원' 보존 전략 사례 연구)

  • Gil, Ji-Hye;Park, Hee-Soung
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.48 no.2
    • /
    • pp.20-33
    • /
    • 2020
  • This study aims to examine the trends in the preservation of urban public parks with a focus on the international movement to acknowledge and preserve the heritage value of urban parks. First, the background in which the concept of "historic urban park" first appeared internationally, as well as the current situation were investigated. Then, the cases of the United Kingdom (UK), the United States (US), and Japan, all of which are already preserving and managing urban public parks, were analyzed. In the ICOMOS-IFLA Document on Historic Urban Public Parks, the International Council on Monuments and Sites (ICOMOS), which is a group of specialists dedicated to the conservation and management of cultural heritage, mentions that it is necessary to maintain the social, intangible, aesthetic, ecological, and civic values of historic urban public parks. In addition, according to ICOMOS, it is necessary to preserve elements of parks, such as space composition, topography, light, and environment. The UK, the USA, and Japan have their own unique characteristics for the background of preserving urban parks, the preservation system, the selection of parks to be preserved, and the elements to be preserved within the park. The UK has categorized parks into certain types from each period and has tried to preserve the common elements in each type. The US has selected the parks to preserve by determining the meaning of the parks itself considering multiple aspects, embracing not only the physical form of the parks, but also the culture, monumentality, and social values. Recently, Japan began the preservation of historic urban parks as a matter of policy and started to implement a preservation policy by investigating modern parks that are believed to be worth preserving. Specialists in cultural heritage preservation have argued that the method of preservation of historic urban parks must differ from that of other parks or gardens. Nonetheless, observing cases in these three countries showed that, regardless of their administrative and legal systems regarding cultural heritage and urban public parks, their policies were still limited to preserving only the physical elements of parks. The direction and methodology for the preservation of historic urban parks must be developed further and elaborated upon in terms of the evolving concept and definition of heritage. Urban parks are where various historic values are accumulated, connoting historical meanings dealing with the memories of the parks and the urban dwellers. This study found that, worldwide, park management has been carried out in a way that the historic values of parks are respected and preserved. This global trend in preserving the historic values of urban public parks has significant implications for the management of urban public parks in Korea that are being formed and renewed repeatedly.

Maintenance dose of electrolyte free polyethylene glycol (PEG) 4000 in Korean children with chronic functional constipation (한국인 소아에서 만성 기능성 변비치료 시 전해질이 함유되지 않은 PEG 4000의 유지용량)

  • Lee, So Hee;Bae, Sun Hwan
    • Clinical and Experimental Pediatrics
    • /
    • v.50 no.12
    • /
    • pp.1212-1216
    • /
    • 2007
  • Purpose : To determine optimal maintenance dose and to evaluation the efficacy and safety of polyethylene glycol 4000 (PEG4000) in children with chronic functional constipation. Methods : This study enrolled 41 children with chronic functional constipation at the Konkuk university hospital August 2005, then June, 2007. Effective maintenance dose was designed as initial amount of PEG4000 that improved frequency, bowel movement, stool consistency for 2 months. Clinical outcome was analysed on the basis of defecation diary. Adverse effect was monitored clinically and biochemically. Results : As a whole group effective maintenance dose of PEG4000 was $0.55{\pm}0.16g/kg/day$ (0.25-0.86). With respect to age, 3-5 years ($0.60{\pm}0.15$), 6-8 years ($0.57{\pm}0.16$), 9-13 years ($0.44{\pm}0.14$) (P=0.024). With respect to body weight, <30 kg ($0.62{\pm}0.14$), ${\geq}30kg$ ($0.41{\pm}0.10$) (P=0.001). One child comlained apigastric soreness on medication. Conclusion : PEG4000 is effective and safe in children with chronic constipation. Initial maintenance dose of PEG4000 was 0.55 g/kg/day.

Comparison of dietary behavior, changes of diet, and food intake between 40~59 years old subjects living in urban and rural areas in Lao PDR (라오스 도시·농촌 지역별 40~59세 주민들의 식행동, 식생활변화 및 식품섭취 비교 연구)

  • Kim, Ji Yeon;Yi, Kyungock;Kang, Minah;Kang, Younhee;Lee, Gunjeong;Kim, Harris Hyun-soo;Hansana, Visanou;Kim, Yuri
    • Journal of Nutrition and Health
    • /
    • v.49 no.2
    • /
    • pp.111-124
    • /
    • 2016
  • Purpose: The current study was conducted for evaluation and comparison of dietary behavior and food intake in different regions of Lao PDR. Methods: The survey was conducted on 979 people aged 40~59 years old living in 25 urban provinces and 25 rural provinces in four districts (VTE Capital-Chanthabuly, Xaysetha, VTE Province-Phonhong, and Thoulakhom) of Laos. General demographic information, health status, and dietary behavior were surveyed using a questionnaire. Results: The literacy ratio (p = 0.000), education level (p = 0.000), asset ownership level (p = 0.000), and government and private employee ratio (p = 0.000) were higher in urban subjects compared with rural subjects. The mean value of weight (p = 0.000), waist circumference (p = 0.000), and diastolic blood pressure (p = 0.009) and alcohol consumption (p = 0.000), self-rated health status (p = 0.001), and the rate of obesity (p = 0.000) were significantly higher in urban subjects compared with rural subjects. However, the rate of current smoker was significantly higher in the rural group (p = 0.023). Meals are becoming more westernized by higher frequency of eating out, consumption of fatty meat and fried or stir-fried food in urban areas compared to rural areas. Urban subjects had relatively better balanced meals compared to rural subjects whereas they consumed insufficient meals per day and consumed meals irregularly compared to rural subjects. Intake of fruit and milk was significantly higher in urban subjects compared with rural subjects. However, the intake of vegetables was significantly higher in rural areas than urban areas. Conclusion: The result of this study showed that the traditional Lao diet is being replaced by an unhealthy western dietary pattern, which may be a risk factor for increasing development of non-communicable disease (NCD) in Lao PDR. Planning of proper personalized nutritional intervention and education in each area is needed to decrease the health risks of NCD.

EFFECTS OF SUSPENDED SILT AND CLAY ON THE MORTALITY OF SOME SPECIES OF BIVALVES (이매패류의 폐사에 미치는 현탁부이의 영향)

  • CHANG Sun-duck;CHIN Pyung
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.11 no.4
    • /
    • pp.227-231
    • /
    • 1978
  • Effects of suspended silt and clay on the survival of the rearing bivalves, Meretrix lusoria, Cyclina sinensis and Mactra veneriformis were studied. During sixty-five days of experimental cultures in different concentrations of suspended silt and clay and in different time of immersions, mortalities of the bivalves were checked every day, and the rates of shell movement and oxygen consumption were measured. In general, the higher the concentration of silt and clay and the longer the immersion time, the earlier the occurence, and the higher the rate of the mortalities of the experimental bivalves. M. veneriformis was subjected to earlier mortality than the others, and the period of $50\%$ mortality was the shortest of the three species (37 days in 1,000 ppm), and longer was that of C. sinensis(42 days). Mortality of M. lusoria occured latest and $50\%$ mortality was seen at the immersion time of 50-51 days. Particularly, M. lusoria showed no mortality in the sea water with 100 ppm of suspended silt and clay, and even in the concentrations of 500 or 1,000 ppm they were able to survive without mortality only if the immersion time was short (12-18 hours per day). M. veneriformis and C. sinensis were also able to survive without mortality when the immersion time was short (12 hours per day) in low concentration (100 ppm). Shell movements of experimental bivalves varied depending upon species. In the case of M. veneriformis the shell was opened continuously and C. sinensis opened their shells frequently, while M. lusoria maintained their shells closed in any experimental concentrations of sea water with suspended silt and clay. Total metabolic activity of M. veneriformis was found to be highest while that of M. lusoria showed the lowest. Little difference of oxygen consumption in excised gill tissue was shown between the control group and the experimental groups. Consequently, it may be stated that the mortality results from a immersion in sea water with high concentration of suspended silt and clay for long-time although the survival rates of the experimental bivalves depend also upon the species, physiological conditions, concentration of suspended silt and clay and immersion time. The survival percentage of bivalve y in relation to the time (day) of immersion X in sea water of suspended silt and clay was found to be: $$M.\;lusoria\;(1,000\;ppm):\;y=7.7\times10^9\;\chi^{-4.77}\;(500\;ppm):\;y=259\chi^{-0.26}$$ $$C.\;sinensis\;(1,000\;ppm):\;y=-21\chi+936\;(\chi<44),\;y=-0.65\;\chi+35\;(\chi>44)$$ $$(500\;ppm):\;y=4.4\times10^5\;\chi^{-2.27}$$ $$M.\;veneriformis\;(1,000\;ppm):\;y=-18\chi+716\;(\chi<39),\;y=-0.89\chi+39\;(\chi>39)$$

  • PDF

Analysis of Set-up Errors during CT-scan, Simulation, and Treatment Process in Breast Cancer Patients (유방암 환자의 모의치료, CT 스캔 및 치료 과정에서 발생되는 준비 오차 분석)

  • Lee, Re-Na
    • Radiation Oncology Journal
    • /
    • v.23 no.3
    • /
    • pp.169-175
    • /
    • 2005
  • Purpose: Although computed tomography (CT) simulators are commonly used in radiation therapy department, many Institution still use conventional CT for treatments. In this study the setup errors that occur during simulation, CT scan (diagnostic CT scanner), and treatment were evaluated for the twenty one breast cancer patients. Materials and Methods: Errors were determined by calculating the differences in isocenter location, SSD, CLD, and locations of surgical clips implanted during surgery. The anatomic structures on simulation film and DRR image were compared to determine the movement of isocenter between simulation and CT scan. The isocetner point determined from the radio-opaque wires placed on patient's surface during CT scan was moved to new position if there was anatomic mismatch between the two images Results: In 7/21 patients, anatomic structures on DRR Image were different from the simulation Image thus new isocenter points were placed for treatment planning. The standard deviations of the diagnostic CT setup errors relative to the simulator setup in lateral, longitudinal, and anterior-posterior directions were 2.3, 1.6, and 1.6 mm, respectively. The average variation and standard deviation of SSD from AP field were 1.9 mm and 2.3 mm and from tangential fields were 2.8 mm and 3.7 mm. The variation of the CLD for the 21 patients ranged from 0 to 6 mm between simulation and DRR and 0 to 5 mm between simulation and treatment. The group systematic errors analyzed based on clip locations were 1.7 mm in lateral direction, 2.1 mm in AP direction, and 1.7 mm in SI direction. Conclusion: These results represent that there was no significant differences when SSD, CLD, clips' locations and isocenter locations were considered. Therefore, it is concluded that when a diagnostic CT scanner is used to acquire an image, the set-up variation is acceptable compared to using CT simulator for the treatment of breast cancer. However, the patient has to be positioned with care during CT scan in order to reduce the setup error between simulation and CT scan.